Story at a Glance.
It’s an interesting question.
Why are some people more compassionate than others? What makes one person altruistic and another self serving? Well, perhaps not surprisingly, the answer lies in our brains.
To be precise the answer lies in our amygdala. The amygdala sits in the temporal lobe of your brain, under the temporal bone, which is roughly behind your ear. If you were to draw a line from the centre of your eye going into your brain and one from the centre of your ear also going into your brain, where those two lines intersect, you’ll find your amygdala.
It’s often referred to as our fear centre, mostly because it’s been mainly studied for that function. It’s easier to study fear than other emotions, in other words it’s easy to study negativity and it’s effects on people. But the truth is the amygdala is actually the area of all of our emotional responses, not just our reaction to fear. The amygdala is geared up to connect to each of the sensory systems in the body. That’s the visual system, the auditory, the olfactory, our sense of touch, our feeling of pain; pretty much all the things we use to process the world around us. And what our amygdala does is work through emotionally how we respond to each of these incoming stimuli.
“The amygdala has long been known as one of the most important components in the neural circuit underlying emotional processing.”1
But it’s not just emotions that the amygdala is employed for. It’s the part of our brain we use to ethically evaluate situations; it’s our moral compass if you will. We also use the amygdala to gauge social situations and our corresponding response to them. And we use it in our learning processes. Pavlov’s Dogs were all using their amygdala’s when they salivated at the sound of the bell.
“In addition, the amygdala is an important component of the neural systems subserving reward learning, social interaction, and moral emotion and reasoning.”2
Recognising facial expressions and what they mean is integral to our ability to empathise and feel compassion for others. And that’s where the amygdala takes the external stimuli, the facial expression and translates that information into an emotional response. For example, if you were to see someone in distress, you would know they were in distress because you would recognise a face that is showing signs of being unhappy or upset. You will process that image and have a corresponding response to it. That’s your visual system relaying information to your amygdala. The distressed person might be crying and your auditory system will relay the distress in their sobs or their shaky voice. These auditory and visual clues are sent to your amygdala and from there in, you react with a corresponding emotional response, a moral response or a social environment response. Your amygdala is weighing up all of these issues and coming up with your reply to the stimulus.
“The ability to recognize the emotions signalled by facial expressions is crucial for making advantageous decisions in a complex social environment”3
That is, you will have an emotional response, or an ethical response, if you have a normal functioning amygdala. If you don’t, that is if you have an under-functioning or damaged amygdala, then you wont. And people who don’t are what we call psychopaths.
“It has also been hypothesized that disturbances in amygdala structure or function may contribute to the social dysfunction and impaired moral decision making in individuals with psychopathy.”4
The studies on psychopaths show that they don’t process facial recognition the same way normal people do. When we see someone in distress it triggers empathetic responses in us. Whereas it doesn’t in psychopaths.
“Psychopathic individuals are particularly viewed as having a specific emotional and interpersonal style that is characterized by the inability to recognize and experience the emotional significance of social events. It was suggested that as a result of their emotional impairments, individuals with psychopathy use a detached, predatory style of antisocial behaviour as a strategy to meet their immediate needs without regard for the consequences.”5
Now we know that the amygdala is the power centre for processing all of the sensory information we receive. So what we start to see with this is that if the amygdala is the mainframe for assessing and processing external stimuli, then something terribly wrong is happening in the amygdalae of psychopaths. When they are synthesising the information for facial recognition or visual and auditory information, when it gets to the amygdala, something is going awry.
“Consistent with the symptoms of psychopathy, one of the most robust findings in individuals with psychopathy is the abnormal psychophysiological responsivity during the viewing of emotional stimuli and aversive conditioning learning, suggesting possible deficits in the neurobiological system that governs emotional response, particularly negative emotions, such as fear and anger.”5
In a study published in the Journal Nature, The Neurobiology of Psychopathic Traits in Youths6 the report notes,
“Psychopathic traits are characterized by core impairments in empathy, particularly in the processing of distress cues, and core impairments in decision making, specifically in prediction error signalling and the representation of reward outcomes and expected value. These impairments are associated with dysfunction in the amygdala.”
“Youths with psychopathic traits and adults with psychopathic traits are notably similar in terms of their functional impairments. Both show reduced psychophysiological responsiveness to the distress of others and impaired recognition of emotional (particularly fearful and sad) expressions, extinction, reversal learning and care-based moral judgement.”
In conclusion the study had this to say about the association of the amygdala and the traits of psychopathy.
“A comparison of structural MRI studies shows that amygdala volume is reduced in both youths and adults with psychopathic traits.”
We know through these studies that the actual size of the amygdala is smaller in psychopaths. Which means what we’re dealing with here is a biological cause for the lack of expression of empathy in psychopaths. They don’t process distress cues the way we do. Basically because their brain’s architecture is different to ours they are not responding the same way someone with a fully functioning amygdala would.
So why all this digging around in the brains of psychopaths if really what we’re interested in is finding out what makes altruistic people tick?
In our follow up article we’ll explore we’ll explain why…
 Fear and the human amygdala. Adolphs R, Tranel D, Damasio H, Damasio AR, J Neurosci. 1995 Sep; 15(9):5879-91.
 The amygdala and reward. Baxter MG, Murray EA. Nat Rev Neurosci. 2002 Jul; 3(7):563-73.
 Impaired recognition of emotion in facial expressions following bilateral damage to the human amygdala. Adolphs R, Tranel D, Damasio H, Damasio A. Nature. 1994 Dec 15; 372(6507):669-72.
 Neural foundations to moral reasoning and antisocial behavior. Raine A, Yang Y. Soc Cogn Affect Neurosci. 2006 Dec; 1(3):203-13.
 Localization of Deformations Within the Amygdala in Individuals With Psychopathy. Dr Yaling Yang, Dr Adrian Raine, Dr Katherine L. Narr, Dr Patrick Colletti, Dr Arthur W. Toga. Arch Gen Psychiatry. 2009 Sep; 66(9): 986–994. doi: 10.1001/archgenpsychiatry.2009.110. PMCID: PMC3192811
 The neurobiology of psychopathic traits in youths. James R. Blair. Nature Reviews Neuroscience 14, 786–799 (2013) doi:10.1038/nrn3577.
 Responses to others’ fear as predictors of empathic behaviours. Abigail A. Marsh. Georgetown University
 Alterations in Resting-State Functional Connectivity Link Mindfulness Meditation With Reduced Interleukin-6: A Randomized Controlled Trial. David Creswell, Adrienne A. Taren, Emily K. Lindsay, Carol M. Greco, Peter J. Gianaros, April Fairgrieve, Anna L. Marsland, Kirk Warren Brown, Baldwin M. Way, Rhonda K. Rosen, Jennifer L. Ferris Biological Psychiatry Journal July 1, 2016. Volume 80, Issue 1, Pages 53–61.